Acquired unilateral upper limb hypertrophy as a late complication of tuberculous meningitis complicated by Chiari 1 malformation and syringomyelia

Case presentation

A 12-year-old woman who suffered tuberculous meningitis (TBM) at the age of 6 months presented with right upper limb panhypertrophy, dissociate anaesthesia, scoliosis and acquired macrocephaly. Her birth was uneventful with a normal head circumference. There was no prior record of headaches, neck or shoulder pain, hoarseness or change in voice, difficulty in swallowing and bowel or bladder involvement.

On examination, she was alert, with a normal mental status. Anthropometry revealed a head circumference of 57 cm (+3 Z-score) consistent with acquired macrocephaly. The cranial nerves were all intact. No nystagmus was observed. Abnormal findings included right upper limb panhypertrophy with a discrepancy circumference of more than 3 cm (figure 1A), scar tissue on the right hand, attributed to burning incidents (figure 1B) and reduced sensation to pain and temperature. The power, muscle tone, deep tendon reflexes, vibration sense and proprioception were all normal. Examination of the back showed a thoracic kyphoscoliosis and lumbar lordosis.

Investigations

MRI revealed cerebral white matter loss with a long-standing right-sided basal ganglia lacunar infarct, communicating hydrocephalus, thinning, and stretching of the corpus callosum, fullness of the foramen magnum with cerebellar tonsillar herniation (8 mm descent) (figure 2A). Spinal MRI demonstrated thoracic scoliosis (figure 2B) as well as syringomyelia extending from C2 to the conus medullaris (figure 2C). Since neuroimaging confirmed the syringomyelia and excluded vascular anomalies and tumours, no further investigations were carried out besides the basic preoperative workup.

Differential diagnosis

The combination of acquired macrocephaly, unilateral limb hypertrophy and dissociate anaesthesia led to a differential diagnosis which included syringomyelia; compression of the lymphatic system by vascular anomaly or tumours, leprosy and filariasis. The latter two conditions were deemed less likely as the associated acquired macrocephaly was non-suggestive. Leprosy has been a notifiable condition in South Africa since 1921 and the WHO elimination target of less than one case per 10 000 population has been achieved.1 In addition, the family never resided or travelled to the eastern coast of South Africa, which was previously considered a leprosy ‘belt’. The overall prevalence of lymphatic filariasis in South Africa is also low and according to the ‘Uniting to Combat Neglected Tropical Disease’ report, mass treatment for lymphatic filariasis is not a requirement in South Africa.2 3

Treatment

The neurosurgical team was consulted for CSF diversion for the hydrocephalus and after reviewing the patient an endoscopic third ventriculostomy (ETV) was performed successfully. Postoperatively, the patient was stable and discharged in 48 hours. Outpatient neurosurgical and neurology follow-up was planned.

Outcome and follow-up

Two years postthird ventriculostomy, the patient has had gradual improvement of clinical symptoms. On her most recent follow-up, she had no headaches and the thermoanaesthesia had resolved. However, the unilateral right limb hypertrophy is persistent with a difference of 3 cm. The paediatric orthopaedics team is closely monitoring her thoracic scoliosis. Postoperative MRI scans demonstrated shrinkage of the syrinx and return of the cerebellar tonsils to their physiological positions (figure 2D).